While a pink sky at night might be a shepherd's delight, London residents were left scratching their heads last night as a mysterious pink cloud drifted over the city.

Bemused bystanders in Mayfair craned their necks to witness the strange alien-like cloud that appeared for just under an hour at around 8:30pm.

It hovered over buildings before breaking up and slowly disappearing.

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Let there be light: The pink clouds drift over London

But after dismissing theories of UFOs and atmospheric phenomenons, the Met Office said the blob was likely to be nothing more than the lights of the city reflected in a cloud.

A spokesman said: "If you have very high cloud, as we did last night, you tend to get odd splodges of low cloud that will reflect the pink or sometimes orangey-pink lights of the city from all angles and stand out from the darkness of the sky.

"It can be truly spectacular to witness."

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